/// <summary>
/// Decodes a message object.
/// The format looks as follows: 28 bit P2P version, 4 bit message type, 32 bit message ID, 8 bit message command,
/// 160 bit senderSocket ID, 16 bit senderSocket TCP port, 16 bit senderSocket UDP port, 160 bit recipientSocket ID, 32 bit content types, 8 bit options.
/// In total, the header is of size 58 bytes.
/// </summary>
/// <param name="buffer">The buffer to decode from.</param>
/// <param name="recipientSocket">The recipientSocket of the message.</param>
/// <param name="senderSocket">The senderSocket of the packet, which has been set in the socket class.</param> // TODO check if true
/// <returns>The partial message where only the header fields are set.</returns>
public static Message DecodeHeader(AlternativeCompositeByteBuf buffer, IPEndPoint recipientSocket, IPEndPoint senderSocket)
{
Logger.Debug("Decode message. Recipient: {0}, Sender: {1}", recipientSocket, senderSocket);
var message = new Message();
int versionAndType = buffer.ReadInt(); // 4
message.SetVersion(versionAndType >> 4);
message.SetType((Message.MessageType)(versionAndType & Utils.Utils.Mask0F)); // TODO does this work? (2x)
message.SetMessageId(buffer.ReadInt()); // 8
message.SetCommand(buffer.ReadByte()); // 9 // TODO check conversion with Java version
var senderId = ReadId(buffer); // 29
int tcpPort = buffer.ReadUShort(); // 31 // TODO check if should be read as short (same as encode)
int udpPort = buffer.ReadUShort(); // 33
var recipientId = ReadId(buffer); // 53
int contentTypes = buffer.ReadInt(); // 57
int options = buffer.ReadUByte(); // 58 // TODO check if should be read as unsigned/signed
message.SetRecipient(new PeerAddress(recipientId, recipientSocket));
message.HasContent(contentTypes != 0);
message.SetContentType(DecodeContentTypes(contentTypes, message));
message.SetOptions(options & Utils.Utils.Mask0F);
// set the address as we see it, important for port forwarding identification
int senderOptions = options >> 4;
var pa = new PeerAddress(senderId, senderSocket.Address, tcpPort, udpPort, senderOptions);
message.SetSender(pa);
message.SetSenderSocket(senderSocket);
message.SetRecipientSocket(recipientSocket);
return(message);
}
/// <summary>
/// Decodes a message object.
/// The format looks as follows: 28 bit P2P version, 4 bit message type, 32 bit message ID, 8 bit message command,
/// 160 bit senderSocket ID, 16 bit senderSocket TCP port, 16 bit senderSocket UDP port, 160 bit recipientSocket ID, 32 bit content types, 8 bit options.
/// In total, the header is of size 58 bytes.
/// </summary>
/// <param name="buffer">The buffer to decode from.</param>
/// <param name="recipientSocket">The recipientSocket of the message.</param>
/// <param name="senderSocket">The senderSocket of the packet, which has been set in the socket class.</param> // TODO check if true
/// <returns>The partial message where only the header fields are set.</returns>
public static Message DecodeHeader(AlternativeCompositeByteBuf buffer, IPEndPoint recipientSocket, IPEndPoint senderSocket)
{
Logger.Debug("Decode message. Recipient: {0}, Sender: {1}", recipientSocket, senderSocket);
var message = new Message();
int versionAndType = buffer.ReadInt(); // 4
message.SetVersion(versionAndType >> 4);
message.SetType((Message.MessageType)(versionAndType & Utils.Utils.Mask0F)); // TODO does this work? (2x)
message.SetMessageId(buffer.ReadInt()); // 8
message.SetCommand(buffer.ReadByte()); // 9 // TODO check conversion with Java version
var senderId = ReadId(buffer); // 29
int tcpPort = buffer.ReadUShort(); // 31 // TODO check if should be read as short (same as encode)
int udpPort = buffer.ReadUShort(); // 33
var recipientId = ReadId(buffer); // 53
int contentTypes = buffer.ReadInt(); // 57
int options = buffer.ReadUByte(); // 58 // TODO check if should be read as unsigned/signed
message.SetRecipient(new PeerAddress(recipientId, recipientSocket));
message.HasContent(contentTypes != 0);
message.SetContentType(DecodeContentTypes(contentTypes, message));
message.SetOptions(options & Utils.Utils.Mask0F);
// set the address as we see it, important for port forwarding identification
int senderOptions = options >> 4;
var pa = new PeerAddress(senderId, senderSocket.Address, tcpPort, udpPort, senderOptions);
message.SetSender(pa);
message.SetSenderSocket(senderSocket);
message.SetRecipientSocket(recipientSocket);
return message;
}
/// <summary>
/// Decodes a <see cref="PeerSocketAddress"/> from a buffer.
/// </summary>
/// <param name="buffer">The buffer.</param>
/// <param name="isIPv4">Whether the address is IPv4 or IPv6.</param>
/// <returns>The <see cref="PeerSocketAddress"/> and the new offset.</returns>
public static PeerSocketAddress Create(AlternativeCompositeByteBuf buffer, bool isIPv4)
{
int tcpPort = buffer.ReadUShort();
int udpPort = buffer.ReadUShort();
IPAddress address;
sbyte[] me;
if (isIPv4)
{
me = new sbyte[Utils.Utils.IPv4Bytes];
buffer.ReadBytes(me);
address = Utils.Utils.Inet4AddressFromBytes(me, 0);
}
else
{
me = new sbyte[Utils.Utils.IPv6Bytes];
buffer.ReadBytes(me);
address = Utils.Utils.Inet6AddressFromBytes(me, 0);
}
return(new PeerSocketAddress(address, tcpPort, udpPort, buffer.ReaderIndex));
}
